4-Toluenesulfonyl chloride → Benzyl 2-phenyl-2-(tosyloxy)acetate

HRID 20854Notes

Reaction equation

HRID 20854 reaction equation
[C:1]1([CH3:11])[CH:6]=[CH:5][C:4]([S:7](Cl)(=[O:9])=[O:8])=[CH:3][CH:2]=1.[OH:12][C@@H:13]([C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1)[C:14]([O:16][CH2:17][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1)=[O:15].C(N(CC)CC)C>CN(C)C1C=CN=CC=1.C(Cl)Cl>[C:24]1([CH:13]([O:12][S:7]([C:4]2[CH:5]=[CH:6][C:1]([CH3:11])=[CH:2][CH:3]=2)(=[O:9])=[O:8])[C:14]([O:16][CH2:17][C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=2)=[O:15])[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1

Participants

6

Reactant 3

HCID 73974-Toluenesulfonyl chlorideHCID 8471TriethylamineHCID 667423Benzyl (2S)-hydroxy(phenyl)acetate

Product 1

HCID 86618475Benzyl 2-phenyl-2-(tosyloxy)acetate

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolvent2×

Conditions

Temperature
0 °C

Procedure

A CH2Cl2 (200 mL) solution of p-toluenesulfonyl chloride (8.65 g, 45.4 mmol) was added dropwise to a cooled (−5° C.) CH2Cl2 (200 mL) solution of (S)-benzyl 2-hydroxy-2-phenylacetate (10.0 g, 41.3 mmol), triethylamine (5.75 mL, 41.3 mmol) and 4-dimethylaminopyridine (0.504 g, 4.13 mmol), while maintaining the temperature between −5° C. and 0° C. The reaction was stirred at 0° C. for 9 hours, and then stored in a freezer (−25° C.) for 14 hours. It was allowed to thaw to ambient temperature and washed with water (200 mL), 1N HCl (100 mL) and brine (100 mL), dried (MgSO4), filtered, and concentrated in vacuo to provide benzyl 2-phenyl-2-(tosyloxy)acetate as a viscous oil which solidified upon standing (16.5 g). The chiral integrity of the product was not checked and that product was used for the next step without further purification. 1H NMR (DMSO-d6, δ=2.5, 500 MHz) δ 7.78 (d, J=8.6, 2H), 7.43-7.29 (m, 10H), 7.20 (m, 2H), 6.12 (s, 1H), 5.16 (d, J=12.5, 1H), 5.10 (d, J=12.5, 1H), 2.39 (s, 3H). RT=3.00 (Cond. 3); >90% homogeneity index; LC/MS: Anal. Calcd. for [M+H]+ C22H20NaO5S: 419.09. found 419.04.

Workup

  1. temperaturewhile maintaining the temperature between −5° C. and 0° C
  2. waitstored in a freezer (−25° C.) for 14 hours
  3. customthaw to ambient temperature
  4. washwashed with water (200 mL), 1N HCl (100 mL) and brine (100 mL)
  5. dry with materialdried (MgSO4)
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-afa6e7eb271848269dfe117eafb45b9d
Source dataset
uspto-grants-2010_06
Patent number
US07745636B2

Reaction notes

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